DENVER (AP)  A plan to scrap the winner-take-all system of allocating electoral votes in Colorado is heading to the ballot in November.

If passed, Amendment 36 would make Colorado the first state to allocate electoral votes proportionately according to the popular vote, rather than giving a winner all of the state's electoral votes.

Secretary of State Donetta Davidson said Friday that supporters have gathered enough signatures to put the measure on the November ballot.

If the proposal had been in place four years ago, Democrat Al Gore would have earned enough electoral votes to go to the White House.

Only two other states do not have winner-take-all systems of casting electoral college votes. Nebraska and Maine give two votes to the winner of each state, and remaining votes are cast to show who won each congressional district.

Republican Gov. Bill Owens and Republican State Party Chairman Ted Halaby have criticized the Colorado proposal, saying it would lessen the state's clout in presidential elections. They warn that candidates will ignore the state and its nine electoral votes if the measure passes.

Julie Brown, campaign director for the Make Your Vote Count effort that supports the measure, dismissed their concerns.

"It begs the question on which is more important — a two-hour presidential stop at a tarmac at Denver International Airport or true representation by the voters."

Katy Atkinson, a spokeswoman for the opposing Coloradans Against a Really Stupid Idea, promised to challenge the measure if it passes and it is applied in this year's presidential race.

The proposal's backers want it to take effect immediately, before Colorado's electoral votes are cast in December.

"They are ripe for a court challenge on this," Atkinson said. "If this is a close race like the one four years ago, we could be thrown into a situation where we are the Florida of 2004. We'd be the laughing stock of the country. All those Florida jokes would be applied to Colorado."

State Sen. Ron Tupa, D-Boulder, tried unsuccessfully in 2001 to change Colorado's electoral system. He said the new ballot initiative is a good idea.

"It will give voters the unique opportunity to reform an outdated electoral system that disenfranchises hundreds of thousands of Colorado voters," he said.

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